One of the most destructive environmental issues around the world is the disposal of construction and demolition (C&D) wastes such as recycled concrete aggregate (RCA), crushed rock (CR), waste glass, and scrap tire. Therefore, using the waste materials in civil projects such as road pavement applications would significantly reduce the consumption of quarry-based virgin materials, alleviate landfill disposal, and minimize greenhouse emissions. Numerous studies have evaluated the effect of crushed glass (CG) for construction applications; however, the effect of CG on the behavior of the crushed recycled materials together with crumb rubber (R) have never been studied for road pavement applications. A series of geotechnical laboratory tests, including modified compaction, unconfined compression strength, California bearing ratio (CBR), and resilient modulus tests, have been done on the blends of different percentages of CG added to the RCA and CR aggregates, together with R for pavement base/subbase applications. The results indicated that the blends of the waste materials, as a low carbon concept, could be a viable and satisfactory alternative solution for future base/subbase applications.

The characteristic features of undrained behavior of a silty sand are investigated for a range of initial conditions $(e,p^{\prime })$ for both isotropic consolidation (CIU) and ${\mathrm{K}}_0$ consolidation (${\mathrm{K}}_0\mathrm{U}$ ). The silty sand contains approximately 10% natural fines. The steady-state line (SSL) for ${\mathrm{K}}_0$ -consolidated specimens is slightly below the SSL for isotropic consolidated specimens. The so-called reverse behavior for silty sand is not observed for CIU, although it is observed in some cases for ${\mathrm{K}}_0\mathrm{U}$ . Earlier studies claimed that the shape and location of the consolidation line with respect to the SSL can explain such behavior. The findings of this study suggest that the liquefaction potential, a key parameter for observing reverse behavior, depends on the state of the soil and shows a unique relation to the state parameter ($\psi$ ) irrespective of the type of consolidation. However, the stress ratio at the triggering of liquefaction, ${\eta }_{IS}$ , and liquefaction resistance, $q_{IS}$ , show slightly different relationships with $\psi$ for isotropic and ${\mathrm{K}}_0$ conditions. This finding has practical importance for estimating liquefaction strengths, triggering of liquefaction, and developing a $\psi$ -dependent constitutive model both for isotropic and ${\mathrm{K}}_0$ consolidation.

Glass-based goods are produced and consumed in relative abundance, making glass a material that is found in most households, thereby leading to its accumulation in alarming quantities throughout the globe and posing an environmental challenge. This being said, glass has been widely acknowledged to possess a variety of desirable physiochemical properties, making it suitable for utilisation as an engineering aggregate. The properties include its non-biodegradable nature, resistance to chemical attack, low water absorption, hydraulic conductivity, temperature-dependent ductility, alterable particle gradation, and its availability in a multitude of forms/chemical compositions. Owing to these properties, glass has been employed in a myriad of civil engineering studies and field trials to assess its efficacy as an engineering aggregate and to provide sustainable management schemes for waste glass. These studies/trials have incorporated glass in many forms, including fine recycled glass (FRG), medium recycled glass (MRG), coarse recycled glass (CRG), glass powder, glass fibres, foamed glass, and glass-based geopolymers. Although the beneficial properties of glass can be exploited in numerous engineering endeavours, this review paper focuses on the possible application of glass to subsurface layers of pavements. In turn, the current study centres on research studies/trials presenting results on the physicochemical, mechanical, and durability aspects of pavement layers (base, subbase, and subgrade) containing pure glass samples or glass as percentage replacements in materials, including but not limited to unbound granular materials (i.e., recycled concrete aggregate (RCA) and crushed rock (CR)) and clay soils. Through the knowledge compiled in this review article, it is reasonable to state that glass shows solid potential as a road pavement material.

The measurement of sap movement in xylem sapwood tissue using heat pulse velocity sap flow instruments has been commonly used to estimate plant transpiration. In this study, sap flow sensors (SFM1) based on the heat ratio method (HRM) were used to assess the sap flow performance of three different tree species located in the eastern suburbs of Melbourne, Australia over a 12-month period. A soil moisture budget profile featuring potential evapotranspiration and precipitation was developed to indicate soil moisture balance while the soil-plant-atmosphere continuum was examined at the study site using data obtained from different monitoring instruments. The comparison of sap flow volume for the three species clearly showed that the water demand of Corymbia maculata was the highest when compared to Melaleuca styphelioides and Lophostemon confertus and the daily sap flow volume on the north side of the tree on average was 63% greater than that of the south side. By analysing the optimal temperature and vapour pressure deficit (VPD) for transpiration for all sampled trees, it was concluded that the Melaleuca styphelioides could better cope with hotter and drier weather conditions.